Try the blood typing game

 blood typing game 

And here is the lesson on co-dominant traits with blood groups as the example  

Lesson on Co-dominance

sex linkage

 SEX LINKED GENES

In the following post, I will refer to the term  "male" and "female".  This refers to people with male sex organs or people with female sex organs.  People with these organs can identify with a diverse range of gender such as:

Man, woman, nonbinary. This gender identify is not presumed by the presence of male or female sex organs

They might also identify as

LGBTQ2S++

The following descriptions are biological descriptions refer to 

male= has male sex organs like testes, producing male gametes such as sperm

female= has female sex organs like ovaries, producing female gametes such as  eggs. 

The sex chromosomes are XX and XY in humans. Some alleles are located on the X chromosome. But very few on the Y chromosome.  Remember that people who are  females have the genotype XX and people who are males have XY.

The Y chromosome carries very little information, only enough to influence the embryo on the path towards male primary and secondary characteristics.

Meanwhile, many RECESSIVE ALLELES are located on the X chromosome, including
1. hemophilia, the inability to clot blood
2. colourblindness inability to tell the difference between red and green colour
3.  baldness

These characteristics are far more common in people with male sex organs  than people with female sex organs because  people with male organs have only one X. And if that X contains the recessive allele, they will show the phenotype.  Meanwhile,people with  female organs may have the recessive and their dominant genes on their other X will protect them.  For example

An example of using a punnet square to calculate probability is here:

Some things to note about sex linkage:  Signs of sex linked alleles are:
1. more genotypic males get the phenotype, but genotypic females can be carriers
2.  males can inherit from mother but not father (because males get their X from mom)
3.  genotypic females have an extra X and this protects them.  Females must be homozygous to show the sex linked phenotype.
Further reading on sex linkage here http://learn.genetics.utah.edu/content/pigeons/sexlinkage/


FYI if you were born a male and you want to know if you're colourblind:  Test yourself here: But careful, if you are a genetically male, you might find out you are colour blind!  Apparently most people find out they are colourblind from their science teacher ! 

 

Colour blind test

Basic practice worksheet going over main concepts

Worksheet B

 

There is a very interesting dress. It has caused major arguments!  This dress causes your cells in your retinas to perceive it to be certain colours depending on the state of your retinas. Of course your genes determine what your retinas are like...but also your retinas change over time too!  

Your perception is also based on whether you think this dress is in shadow or light...Try this, 

 I would like you to ask  20 people you know "What colours do you see on this dress:  Is it :  

A. GOLD AND WHITE 

B.  BLACK AND BLUE

C.  GOLD AND BLUE

D.  NONE OF THE ABOVE...THEN what colour is it?  

What are the characteristics of the people who are more likely to say that it is any of the choices above?   

Remember you can poll people without meeting face to face. Ask a variety of people including old, young, male, female...put your results on a table and hypothesize why people see different colours

Co-dominance and human blood groups

 get ready for a quiz on this material next wednesday

BLOOD TRANSFUSIONS NEED TO MATCH THE DONOR BLOOD WITH RECIPIENT BLOOD SO THAT THE RECIPIENT WON'T MAKE ANTIBODIES AGAINST THE BLOOD DONATION

You have heard that blood type is important for blood transfusions. That is because the immune system will always attack foreign protein.  Surface proteins on cells and microbes are called ANTIGENS.  Your immune system will generate ANTIBODIES to fight antigens .  Antigens cause foreign cells to agglutinate so they can be "eaten" by white blood cells (opsonization) 

BESIDES A and  B ANTIGENS, your blood cells can also have Rh Factor antigens

When blood is rejected, it undergoes "AGGLUTINATION", this is when blood clumps up into blood clots.  

Anyone with NO RH factor will reject a donation from RH+ blood:

People with RH factor have Rh positive blood.   Type A+ has A proteins and Rh proteins. 

People who are:

type A+ can receive Type A-, A+ and O+ and O- blood

type B+ can receive type B-, B+ and O+ and O- blood

type AB+ can receive ALL TYPES OF BLOOD 

type O+ can only receive O+  and O- blood 

People who are:

Type A- can receive A-, O- blood

Type B- can receive B-, O- blood

Type AB- can receive A-,B-, O- blood 

Type O-  can only receive O- blood BUT YOU CAN DONATE O- TO ALL BLOOD TYPES

You can practice giving the right kind of blood on this website 

https://educationalgames.nobelprize.org/educational/medicine/bloodtypinggame/

HUMAN BLOOD GROUP GENETICS 

The Alleles that make the human blood group antigens are codominant: 

A is codominant to B
A is dominant over O
B is dominant over O

Possible genotypes:

heterozygous AB blood gives both type A protein and type  B protein on the erythrocytes.

homozygous AA gives blood type A  protein on the erythrocytes
homozygous BB is blood type B protein on the erythrocytes

Heterozygous AO is gives blood type A
Heterozygous BO is blood type B

homozygous recessive OO gives blood type O .

There is  neither A or B on erythrocytes.

Blood type is heritable and that means you can sometimes deduce genotype by looking at phenotype. Here is a sample question:

GENETICS OF RH FACTOR 

Rh factor is the dominant trait.  If you assign Rh=R then 

Rh+. is   RR or Rr

Rh - is rr

Genetics intro: How to draw punnet squares and calculate probability

Watch my introduction to Genetics video and make notes on it. Note that there is an important correction in the video:  

CORRECTION: I would like to clarify that  the gender identity " girl" or "boy" does not necessarily correspond to the genotypes XX and XY.  Someone with female gametes  and genotype XX can be: a trans man, a cis woman, a nonbinary person or an agender person.  Also genotype XY can be: a trans woman, a cis man, a nonbinary person or an agender person.  There is one section of the video where I refer to a "girl" as xx and a "boy as xy.  This is incorrect.

Dominant and recessive traits

 these are the  Genotypes for the following traits:

Dominant trait                            recessive trait

Earlobe attachment EE, or Ee.    unattached  ee

Tongue rolling TT or Tt              no tongue rolling tt

Cleft chin   CC or Cc                  no cleft cc

Widow’s peak WW or Ww.          straight hairline ww                    

Natural curl. NN.         straight hair nn.          wavy Nn       

Dimples DD or Dd            no dimples. dd

Righty RR   or Rr.          lefty rr

Freckles FF  or Ff           no freckles ff

Blood type.  AA  or Ao 

                    BB or Bo

                    AB 

                    oo 

internal ovaries  XX       internal testes XY.  

 

(NOTE THAT internal organs do NOT determine Gender identity)

Mitosis Review

 Although you studied mitosis and meiosis last year, it is worth a look again to make sure you have all the steps down correctly.  It will help you to understand our next unit which is Genetics.  This video explains how alleles are connected to the steps of mitosis and meiosis.  I also assume this is familiar from last year.

Your teacher will review these steps, explaining some of the complex parts and  give you time to answer the questions.  Next, your teacher will review the answers to the questions.  After this you will do a creative assignment to demonstrate that you understand this material.  

Please watch this video


Answer the following questions on your own paper and hand this in. 

 Answer in full sentences and draw your answers.  Draw in ink or photograph a model using lego, string or other material

1.  What is Chromatin?  How many strands are there in a human?
2.  How many chromatids are there in a human?
3.  What is the 2n  or diploid number?
4.  What is mitosis used for?
5.  What is meiosis used for?
6.  Define "Gamete"
7.  What is the Haploid number?
8.  What organ makes sperm, what makes egg?
9.  How many chromatids are in a sperm or egg?
10 Draw a fertilization
11.  Draw how sperm cells are made using the number 46 to represent the chromatid number.
12.  Draw and label Chromatin, Chromatid, Sister chromatids, Chromosome.  And show me a homologous chromosome
13.    Draw a mitosis with 2n= 6.  Label the stages in detail. Remember to draw Interphase and show chromatins.
14.  Draw a meiois with 2n=6.   Label the stages.
Again, draw interphase and show the chromatin.
15a. Why does crossing over happen during prophase I?
15b.  What is primary nondisjunction.  What can happen to the chromatid number?

16.  The word chromosome is very tricky it's true definition is:

1 chromosome = 2 identical sister chromatids joined together in a centromere,
What is the other definition and why can it be a very tricky word?

17.  Write the steps of meiosis and mitosis side by side.   (this is at the end of the video)

You can also take a look at this resource.  It is meiosis and mitosis from a college level text book.  This is extended reading for those who are interested in going through biology.  I think many of you can actually handle this level.